A method of coating a layer of an yttrium vanadate phosphor contained in a fluorescent lamp with Y.sub.2 O.sub.3 or Al.sub.2 O.sub.3 and lamps made therefrom

摘要

A fluorescent lamp containing a Y.sub.2 O.sub.3 or Al.sub.2 O. sub.3 coating on a layer of yttrium vanadate phosphor and a method of coating the layer of the yttrium vanadate phosphor with a continuous protective coating of Y.sub.2 O.sub.3 or Al.sub.2 O.sub.3 is described. The method comprises applying a coating of a metal, such as yttrium or aluminum, on the yttrium vanadate phosphor then lehring the metallic coating at about 500 C. to about 625 C. to form a continuous protective coating of Y.sub.2 O.sub.3 or Al.sub.2 O.sub.3 overlaying the layer of phosphor.